Radio controlled garage door openers have long been known and are in wide use, being particularly popular in residential use. Such a garage door opener permits the householder by actuation of his hand-hand transmitter and without leaving the comfort and safety of his automobile, to close the garage door against the weather and unwanted intruders as he drives away from his home and upon returning to open the garage door, drive into the garage, and once again close the garage door.
In view of their convenience and security advantages, such radio controlled garage door openers are in many neighborhoods found at closely adjacent homes and many persons traveling through the neighborhood may have hand-held transmitters. To avoid opening of the garage door of one person by the transmitter of another, either through honest inadvertence or dishonest intent, manufacturers have for some time offered radio controlled garage door openers with additional circuitry permitting a given transmitter-receiver pair to be preset to operate with any one of a number of differing radio signals. This makes it less likely that the radio signal required to actuate one garage door would be provided by the transmitters of others. U.S. Pat. No. 4,141,010 issued to Messrs. Umpleby and Apple, discloses an example of a system having such a presettable radio signal, particularly wherein the transmitted radio signal is modulated by a train of ten pulses which are width controlled in a preselected manner.
Despite the long and widespread use of such radio controlled garage door opening systems and despite the now common use of relatively complex transmitter circuitry to permit the individual to select a substantially unique form of transmitted signal, from among a large number of possibly selectable radio signals, disadvantages still remain in existing transmitters of this type, which the present invention is intended to overcome.
Thus, the objects and purposes of this invention include provision of:
A radio controlled garage door opener in which activation of an audible signal at the transmitter provides the user with a direct indication of transmitter operation.
An apparatus, as aforesaid, in which the presence of, or absence of, such signal indicates that the transmitter battery is good or bad while also indicating whether or not the transmitter is enabled to transmit a radio frequency (RF) signal.
An apparatus, as aforesaid, in which the user of the transmitter is provided with an audible alarm related in wave form to the signal modulating the RF oscillator of the transmitter and which, particularly in the case of a transmitter employing a modulating pulse train of distinctive character, provides the person operating the transmitter with a pulsing sound distinctively different from normal environmental sounds, and in which the user of the transmitter is alerted to inadvertent turning on of the transmitter.
An apparatus, as aforesaid, in which a continuous or uncontrolled audible tone alerts the user of the transmitter to the presence of a stuck or defective manual actuation switch on the transmitter, and for example avoids running down of the battery of the transmitter due to jamming of the transmitter into a tight glove compartment in a vehicle or in the purse of the user.
Other objects and purposes of the invention will be apparent to persons acquainted with apparatus of this general type upon reading the following specification and inspecting the accompanying drawings.